ubuntustudio-controls fail to write NICE settings

[Trulan Martin]

Binary package hint: ubuntustudio-controls

Ubuntu Studio Controls fails to write NICE settings to /etc/security/limits.conf. Memlock and raw1394 are handled correctly. When I uncheck nice and click 'apply', it says:
Removing settings
No matches in file

ProblemType: Bug
Architecture: amd64
Date: Sat Oct 17 12:39:21 2009
DistroRelease: Ubuntu 9.10
NonfreeKernelModules: nvidia
Package: ubuntustudio-controls 0.4.6
PackageArchitecture: all
ProcEnviron:
 PATH=(custom, no user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
ProcVersionSignature: Ubuntu 2.6.31-9.152-rt
SourcePackage: ubuntustudio-controls
Uname: Linux 2.6.31-9-rt x86_64

[ttoine (ttoine)]

I can confirm the bug on i386 too, on Karmic Beta.

If using Ubuntu Studio Controls to set Nice, editing the file /etc/security/limits.conf will confirm that it as not been writen in after clicking "Apply".

Concerning Memlock, there is a bug too: it writes in /etc/security/limits.conf the amount of Kb and add unlimited, whatever the value configured.

For setting up raw1394 access, it seems to be good.

[Eric Hedekar (stochastic)]

ttoine, please file a separate bug report for the Memlock problem you've noticed.

[ttoine (ttoine)]

Eric,

I won't file a separate bug as there is only one bug: "Ubuntu Studio
Controls don't write well the informations in
/etc/security/limits.conf". Or more simply, "Ubuntu Studio Controls
don't work well". It would be better to rename this bug than to open
several others in Launchpad.

This GUI tool should add too the rtprio configuration like that :
@audio - rtprio 99
If it is configured by a script when installing Ubuntu Studio Desktop or
something like that, it is not the better way. Ubuntu Studio Controls
should do it, as not all Ubuntu multimedia users want the Ubuntu Studio
Desktop to be installed. But most of users may consider that Ubuntu
Studio Controls could be a good GUI if it avoid editing configuration
text files at all.

An other bug of the GUI is that nice value is not a percentage, as
indicated. It is just a value... And perhaps, it should be good to have
an explanation about what are max and min values, and that a low value
(under 0) provide "more" real time. With something a simple "?" button,
for example.

In order to close this answer, I remember that the easiest way to get
good right access to raw1394 is to add the user name in "disk" group in
Hardy, and in "video" group in Karmic Beta. Of course, it needs the user
to be member of the "disk" or "video" group. This is perhaps not the
"legacy" way to do it, but it works well. And could be better than
editing a important configuration file with a bad script.

Toine

[autostatic (autostatic)]

Tried to finetune my Karmic installation with the help of Ubuntu Studio Controls. These were my findings:
- When I tick 'enable raw 1394' I'm confronted with a message about privilages. English is not my native tongue but shouldn't it be privileges instead of privilages?
- Ubuntu Studio Controls messes up my /etc/security/limits.conf. After clicking 'Apply' it looks like this:

@audio - rtprio 90 # maximum realtime priority

unlimited # maximum locked-in-memory address space (KB)

So only the rtprio line got added correctly, the other lines to configure the nice and memlock settings are either not added or just garbled.
- Ubuntu Studio Controls messes up my /lib/udev/rules.d/50-udev-default.rules. After enabling raw 1394 this gets added to the file:

# do not delete static device nodes
ACTION=="remove", NAME=="", TEST=="/lib/udev/devices/%k", OPTIONS+="ignore_remove"
KERNEL=="raw1394", GROUP="video"
ACTION=="remove", NAME=="?*", TEST=="/lib/udev/devices/$name", OPTIONS+="ignore_remove"

The raw1394 just gets added somewhere, in this case as the last but one line. In my opinion it would look cleaner if this line gets added to the Firewire stanza. Or that a seperate file gets created, like 50-raw-firewire.rules, with this line in it, to make sure this line doesn't get deleted by any future updates that might overwrite the 50-udev-defaults.rules file. I'm also wondering if nothing got deleted from the 50-udev-defaults.rules file.
- After using Ubuntu Studio Controls I still couldn't use my Firewire device because 1. I was not a member of the Video group, 2. the raw1394 module still needs to get loaded and 3. /dev/raw1394 wasn't chgrp'd to video. Maybe it's an idea to integrate these steps in a future version?

Best,

Jeremy

[Len Ovens (len-ovenwerks)]

Setting nice does not change audio stability or latency in any way and therefore does not need to be set.